tanstaafl, thank you. I found the tab Preferences -> Security -> Junk tab. The settings are such that messages marked as junk are moved to the account's Junk folder. And I have enabled adaptive junk filter logging.I have both address books (Personal Address Book and Collected Addresses) checkmarked to be whitelisted.

The advice which I received yesterday, to remove the msf files and have them re-created, did not help. After doing this did still email from whitelisted addresses get moved to the Junk folder.

You'll want to see what the junk log indicates. If there is not an entry in the filter log for the message you don't want moved..- Do you have a filter (tools > filters) set to move the messages?- The message in the junk folder has a flame in the junk status column, or no?

I notice that the following sequence takes place: a new message gets downloaded from the mail server (Yahoo, in my case). If this message is considered by Thunderbird to be junk is it moved directly to the Junk folder. This message gets a flame in the junk status column. Upon clicking this flame is the message moved to the Inbox folder. But then it will get a flame again. It will not be moved to the Junk folder but remains in the Inbox folder, albeit "flamed" and considered junk.

One more update from me: I notice that messages which are considered spam by Thunderbird are not placed in the folder called Junk, but in the folder called Bulk Mail.

And I can confirm that the issue has not yet gone away: I still receive some YouTube notifications in my Inbox (these are not marked as spam), and some notifications in the Bulk Mail folder (these are marked as spam). The address where these notifications are sent from is in my address book and this address book is whitelisted.

My conclusion is that unfortunately Thunderbird is not able to determine spam mail correctly. I still have the issue that genuine messages, from genuine senders, are considered spam. With genuine senders I mean senders whose email addresses are listed in my address book. This is also shown by a yellow star next to the sender's name in the header of a message.So I want to disable all Thunderbird spam filtering. For each of the accounts have I unticked the box "enable adaptive junk mail controls for this account". And have unticked the box "move new junk messages to:".On top of this have I unticked, in the global preferences on Security, the box "enable adaptive junk filter logging".Whether necessary or not, have I rebooted the machine and observed the behaviour for a couple of days.Nevertheless is Thunderbird stubborn with new messages: it classifies certain genuine messages as junk and moves these messages into a junk folder.How can I prevent Thunderbird from doing this? How can I prevent Thunderbird from classifying any incoming email as spam and from moving messages from the inbox to the spam folder?

It sounds as though the action you are trying to prevent is taking place on the server side, before the messages are ever seen by Thunderbird. Thunderbird does not use the term SPAM in anyway nor does it use "Bulk Mail" as the name for a folder. That indicates the folder name is derived from the IMAP server, not from Thunderbird itself.

The mail accounts are Yahoo mail accounts. I will verify during the coming days with the online Yahoo mail website whether it is Yahoo who marks and moves these messages, or whether it is Thunderbird.

Interesting side effect: the notification from this forum about your reply also ended up in a spam, junk or bulk mail folder (I forgot exactly where it ended). I marked it as not junk and it moved to the inbox. However, even after marking it in Thunderbird as not junk is it automatically rebranded as junk some time later in Thunderbird.

This bug report seems to be the exact opposite (the inverse) of what I have been experiencing. It discusses people who want to mark a message as junk, whereas I want to mark certain messages as not junk.As an example: I see an email from YouTube with a notification of a new video being placed by Yahoo in the bulk mail folder. So Yahoo considers it a spam message. I see this message in Thunderbird in the bulk mail folder, with the junk flame lit. I think that it is not spam so I click on the flame. The message gets moved by Thunderbird to the inbox, and the flame is "unlit". However, after a while the flame becomes lit, but the message remains in the inbox.

I have started to pay more attention to exactly which program places a genuine message in what junk/spam folder. What is the role of Thunderbird, and what is the role of Yahoo in all this? I now see that Yahoo places some YouTube notifications in the inbox, and others in the bulk mail folder. Also the notification messages from this forum are placed by Yahoo in the bulk mail folder. I then use the Yahoo online mail interface to mark those tagged messages as "not spam" and they are moved by Yahoo to the inbox. And Thunderbird follows: the messages are moved to the inbox and their flames are unlit. Maybe I need to train the Yahoo filter a bit better. Apparently I cannot do that by using Thunderbird, but have to log into Yahoo each time when a message is incorrectly labelled as spam.

Its easier if you configure the Yahoo IMAP account in Thunderbird to use the bulk mail folder as the "junk" folder. Mine has just spam in it as Yahoo doesn't seem to have separate folders for spam and bulk (but legitimate) mail.

I don't understand why you are using webmail to review messages for spam. Do it all in Thunderbird. If the message was incorrectly placed in bulk mail mark it as not junk. If I mark as not junk a message in bulk mail it is moved to the inbox.

tanstaafl wrote:I don't understand why you are using webmail to review messages for spam. Do it all in Thunderbird. If the message was incorrectly placed in bulk mail mark it as not junk. If I mark as not junk a message in bulk mail it is moved to the inbox.

It is this function (mark as not junk) which is not working properly in Thunderbird. The message does indeed get moved from Bulk Mail to Inbox. However, it gets again marked as junk and therefore is the formatting garbled and the message not properly visible.However, if I go into Yahoo online mail and there mark the message as not spam, is it moved to the inbox and is it no longer being considered junk in Thunderbird. The html formatting of the message is now intact and I can read it properly.